Improvement in lightning-rods



N. VAN LOON.

LIGHTNING ROD.

N0.188,444. Patented March13, 1877.

WITNESSES T 2/ olgVENTOR m W M; I ,2 330770 We w r ATTORNEYS,

UNITED STATES PATENT rrrgcn NICHOLAS VAN LOON, OF ST. CLOUD, MINNESOTA.

lMPRO VEMENT IN LIGHTNING-RODS Specification forming part of LettersPatent No. 188,444, dated March 13. 1877; application tiled J anuary 20,1877.

tion of a perspective view of my lightning-rod,

and Fig. 2 is a transverse sectional view of the same.

This invention relates to that class of light ning-rods in which astraight central core is surrounded by twisted wires.

Thenature of said invention consists in combiningwith said wires andcore, which are iron,

- a coppersheath or tube, enveloping said core,

and made concentric therewith in cross-section.

In the accompanying drawings, A designates the central iron core of mylightningrod. B designates a copper cylindrical sheath or envelope,concentric with said core in crosssection, and fitted closely thereon. Gdesignates a number of iron wires, which are tightly wound about saidsheath, as shown in Fig. 1.

This construction has all the advantages of the ordinary cable lightningrods, and some additional ones, which arise from the use of saidcylindrical sheath B. Said sheath increases the conducting capacity ofthe rod nearly as much as if both it and core A were made of copper inone piece, since electricity.

prefers the surface, while its expense is much less than that of such acore.

Said sheath is protected, by twisted iron wires 0, from the weather, andfrom accidental or unintentional injury, and thus remains bright andwhole, forming an excellent conductor. In like manner it protects thecore A, so that in order to destroy the efficacy of my compoundlightning-rod it becomes necessary to cut through several successivelayers of heterogeneous conducting material.

What I claim as new, and desire to secure by Letters Patent, is

The combination of copper sheath B with iron core A and twisted ironinclosing wires 0, substantially as and for the purpose set forth.

In testimony that I claim the above I have hereunto subscribed my namein the presence of two witnesses.

NICHOLAS VAN LOON. Witnesses:

L. A. EVANS, Tnos. U. McOLURE.

